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	<div id="winchm_template_title">IG_DUMP_SYMBOL_INFO</div>
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	<div id="winchm_template_content"><div id="mainSection"><p>The IG_DUMP_SYMBOL_INFO <a href="#Bookmark1075"><b>Ioctl</b></a> operation provides information about the type of a symbol.  When calling <b>Ioctl</b> with <i>IoctlType</i> set to IG_DUMP_SYMBOL_INFO, <i>IpvData</i> should contain an instance of the SYM_DUMP_PARAM structure.</p>
<pre class="syntax" xml:space="preserve"><code>typedef struct _SYM_DUMP_PARAM {
    ULONG  size;
    PUCHAR  sName;
    ULONG  Options;
    ULONG64  addr;
    PFIELD_INFO  listLink;
    union {
        PVOID  Context;
        PVOID  pBuffer;
    };
    PSYM_DUMP_FIELD_CALLBACK CallbackRoutine;
    ULONG  nFields;
    PFIELD_INFO  Fields;
    ULONG64  ModBase;
    ULONG  TypeId;
    ULONG  TypeSize;
    ULONG  BufferSize;
    ULONG  fPointer:2;
    ULONG  fArray:1;
    ULONG   fStruct:1;
    ULONG  fConstant:1;
    ULONG  Reserved:27;
} SYM_DUMP_PARAM, *PSYM_DUMP_PARAM;
</code></pre>
<h2><a id="Members"></a><a id="members"></a><a id="MEMBERS"></a>Members</h2>
<p></p>
<dl>
<dt><a id="size"></a><a id="SIZE"></a><b>size</b></dt>
<dd>
<p>Specifies the size, in bytes, of this structure.  It should be set to <code>sizeof(SYM_DUMP_PARAM)</code>.</p>
</dd>
<dt><a id="sName"></a><a id="sname"></a><a id="SNAME"></a><b>sName</b></dt>
<dd>
<p>Specifies the name of the symbol to lookup.</p>
</dd>
<dt><a id="Options"></a><a id="options"></a><a id="OPTIONS"></a><b>Options</b></dt>
<dd>
<p>Specifies the flags that determine the behavior of this <b>Ioctl</b> operation.  For a description of these flags, see <a href="#Bookmark1077"><b>DBG_DUMP_XXX</b></a>.</p>
</dd>
<dt><a id="addr"></a><a id="ADDR"></a><b>addr</b></dt>
<dd>
<p>Specifies the address of the symbol.</p>
</dd>
<dt><a id="listLink"></a><a id="listlink"></a><a id="LISTLINK"></a><b>listLink</b></dt>
<dd>
<p>Specifies the field that contains the next item in a linked list.  If the symbol is an entry in a linked list, this <b>Ioctl</b> operation can iterate over the items in the list using the field specified here as the pointer to the next item in the list.  The type of this structure is <a href="#Bookmark1078"><b>FIELD_INFO</b></a>.</p>
<p>The callback function specified in the <b>fieldCallBack</b> member of this structure is called, during this <b>Ioctl</b> operation, for each item in the list.  When it is called, it is passed this <b>linkList</b> structure with the members filled in for the list entry along with the contents of the <b>Context</b> member.</p>
<p>DBG_DUMP_LIST should be set in <b>Options</b> to tell this <b>Ioctl</b> to iterate over the list.</p>
</dd>
<dt><a id="Context"></a><a id="context"></a><a id="CONTEXT"></a><b>Context</b></dt>
<dd>
<p>Specifies a pointer that is passed to the callback function in the <b>CallbackRoutine</b> member and to the callback functions in the <b>fieldCallBack</b> member of the <b>linkList</b> and <b>Fields</b> members.</p>
</dd>
<dt><a id="pBuffer"></a><a id="pbuffer"></a><a id="PBUFFER"></a><b>pBuffer</b></dt>
<dd>
<p>Specifies a buffer that receives information about the symbol.  This buffer is only used if the DBG_DUMP_COPY_TYPE_DATA flag is set in <b>Options</b>.  The size of this buffer is specified in <b>BufferSize</b>.</p>
</dd>
<dt><a id="CallbackRoutine"></a><a id="callbackroutine"></a><a id="CALLBACKROUTINE"></a><b>CallbackRoutine</b></dt>
<dd>
<p>Specifies a callback function that is called by the engine.  The engine provides the callback function with information about the symbol and its members.</p>
</dd>
<dt><a id="nFields"></a><a id="nfields"></a><a id="NFIELDS"></a><b>nFields</b></dt>
<dd>
<p>Specifies the number of entries in the <b>Fields</b> array.</p>
</dd>
<dt><a id="Fields"></a><a id="fields"></a><a id="FIELDS"></a><b>Fields</b></dt>
<dd>
<p>Specifies an array of <a href="#Bookmark1078"><b>FIELD_INFO</b></a> structures that control the behavior of this operation for individual members of the specified symbol. See FIELD_INFO for details.</p>
</dd>
<dt><a id="ModBase"></a><a id="modbase"></a><a id="MODBASE"></a><b>ModBase</b></dt>
<dd>
<p>Receives the location in the target's memory of the start of the module that contains the symbol.</p>
</dd>
<dt><a id="TypeId"></a><a id="typeid"></a><a id="TYPEID"></a><b>TypeId</b></dt>
<dd>
<p>Receives the type ID of the symbol.</p>
</dd>
<dt><a id="TypeSize"></a><a id="typesize"></a><a id="TYPESIZE"></a><b>TypeSize</b></dt>
<dd>
<p>Receives the size, in bytes, of the symbol in the target's memory.</p>
</dd>
<dt><a id="BufferSize"></a><a id="buffersize"></a><a id="BUFFERSIZE"></a><b>BufferSize</b></dt>
<dd>
<p>Specifies the size, in bytes, of the <b>pBuffer</b> buffer.</p>
</dd>
<dt><a id="fPointer"></a><a id="fpointer"></a><a id="FPOINTER"></a><b>fPointer</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the symbol is a pointer.  <b>fPointer</b> is <b>FALSE</b> if the symbol is not a pointer.  It is 1 if the symbol is a 32-bit pointer and 3 if the symbol is a 64-bit pointer.</p>
</dd>
<dt><a id="fArray"></a><a id="farray"></a><a id="FARRAY"></a><b>fArray</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the symbol is an array.  <b>fArray</b> is <b>FALSE</b> if the symbol is not an array and <b>TRUE</b> if it is.</p>
</dd>
<dt><a id="fStruct"></a><a id="fstruct"></a><a id="FSTRUCT"></a><b>fStruct</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the symbol is a structure.  <b>fStruct</b> is <b>FALSE</b> if the symbol is not a structure and <b>TRUE</b> if it is.</p>
</dd>
<dt><a id="fConstant"></a><a id="fconstant"></a><a id="FCONSTANT"></a><b>fConstant</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the symbol is a constant.  <b>fConstant</b> is <b>FALSE</b> if the symbol is not a constant and <b>TRUE</b> if it is.</p>
</dd>
</dl>
<h2><a id="Return_Value"></a><a id="return_value"></a><a id="RETURN_VALUE"></a>Return Value</h2>
<p>If this <b>Ioctl</b> operation succeeds, the return value from <b>Ioctl</b> is zero; otherwise, it is an <a href="#Bookmark1081"><b>IG_DUMP_SYMBOL_INFO error code</b></a>.</p>
<h2>Remarks</h2>
<p>The parameters for the IG_DUMP_SYMBOL_INFO <a href="#Bookmark1075"><b>Ioctl</b></a> operation are the members of the SYM_DUMP_PARAM structure.</p>
<p>This <b>Ioctl</b> operation looks up the module information for the symbol, loading module symbols if possible.</p>
<p>If <b>nFields</b> is zero and DBG_DUMP_CALL_FOR_EACH is set in <b>Options</b>, the callback function specified in <b>CallbackRoutine</b> is called for every field in the symbol.</p>
<p>If <b>nFields</b> is non-zero and DBG_DUMP_CALL_FOR_EACH is set in <b>Options</b>, callbacks are only made for those fields matching the <b>fName</b> member of one of the <b>Fields</b> elements.  If a field matches a <b>fName</b> member and the <b>fieldCallBack</b> member is not <b>NULL</b>, the callback function in  <b>fieldCallBack</b> is called; if it is <b>NULL</b>, the callback function in <b>CallbackRoutine</b> is called instead.</p>
<h2>Requirements</h2>
<table>
<tr>
<th width="30%">
<p>Header</p>
</th>
<td width="70%">
<dl>
<dt>Wdbgexts.h (include Wdbgexts.h, Wdbgexts.h, or Dbgeng.h)</dt>
</dl>
</td>
</tr>
</table>
<h2><a id="see_also"></a>See also</h2>
<dl>
<dt><a href="#Bookmark1075"><b>Ioctl</b></a></dt>
<dt><a href="#Bookmark1081"><b>IG_DUMP_SYMBOL_INFO Error Codes</b></a></dt>
<dt><a href="#Bookmark1077"><b>DBG_DUMP_XXX</b></a></dt>
<dt><a href="#Bookmark1078"><b>FIELD_INFO</b></a></dt></dl></div></div>	
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